Zend Framework是Zend推出的網頁框架，可以幫助網站的開發速度及維護，目前已經推出到1.5版本，如果有在使用PHP開發網站，這是一個不錯的開發工具，而且還是完全免費喔！

目前已包含數十種工具，例如MVC、RSS、AJAX(透過JSON)、DB、Cache、Auth、還有許多的API....等

Zend Framework是用於PHP開發Web應用程序和Web Service程序的高品質開放原始碼框架。

利用PHP自身特性，Zend Framework有很高的易用性和強大的功能。它提供了先進、健壯和安全的開發網站的解決方案。
以下是ZF官網上的介紹

Why Zend Framework?

Extending the art & spirit of PHP, Zend Framework is based on simplicity, object-oriented best practices, corporate friendly licensing, and a rigorously tested agile codebase. Zend Framework is focused on building more secure, reliable, and modern Web 2.0 applications & web services, and consuming widely available APIs from leading vendors like Google, Amazon, Yahoo!, Flickr, as well as API providers and cataloguers like StrikeIron and ProgrammableWeb.

Expanding on these core themes, we have implemented Zend Framework to embody extreme simplicity & productivity, the latest Web 2.0 features, simple corporate-friendly licensing, and an agile well-tested code base that your enterprise can depend upon.

Extreme Simplicity & Productivity
We designed Zend Framework with simplicity in mind. To provide a lightweight, loosely-coupled component library simplified to provide 4/5s of the functionality everyone needs and that lets you customize the other 20% to meet your specific business needs. By focusing on the most commonly needed functionality, we retain the simplified spirit of PHP programming, dramatically lower the learning curve, and your training costs – so developers get up-to-speed quickly. We do this with:

Extensible and
well-tested code base Flexible architecture No configuration files
necessary to get going Frameworks and best practices mean reduced training costs and quicker time-to-market – important factors in adoption decisions. Built so you can pick and choose just the pieces you need to turbocharge your web applications – all your developers know where to find their PHP / Zend Framework code, speeding new development and reducing maintenance costs.

Latest Web Development Features
AJAX support through JSON – meet the ease-of-use requirements your users have come to expect
Search – a native PHP edition of the industry-standard Lucene search engine
Syndication – the data formats & easy access to them your Web 2.0 applications need
Web Services – Zend Framework aims to be the premier place to consume & publish web services
High-quality, object-oriented PHP 5 class library – attention to best practices like design patterns, unit testing, & loose coupling
Friendly & Simple Licensing, Safe for the Enterprise
Based on the simple and safe new BSD license, with Zend Framework's License, you rest assured that your code is compliant, unimpeachable, and protected as you see fit. We also require all contributors to the open source Zend Framework to complete and sign a Contributor License Agreement (CLA) — which is based on the standard open-source Apache license — protecting your own intellectual property (that is, your added-value) built on Zend Framework.

Fully Tested – Extend Safely and Easily
Tested. Thoroughly. Enterprise-ready and built with agile methods, Zend Framework has been unit-tested from the start, with stringent code coverage requirements to ensure that all code contributed has not only been thoroughly unit-tested, but also remains stable and easy for you to extend, re-test with your extensions, and further maintain.

http://framework.zend.com/